Unity Errors - adding FP Asset - Fix Old vs New Input Errors

Adding the Unity FP Starter Asset and getting errors for the Event System? It's a New Input vs Old input system and I'll show how to fix it here. #shorts ► Unity First Person Controller - https://assetstore.unity.com/packages/essentials/starter-assets-first-person-character-controller-196525?aid=11

You add a first person character controller asset to your project and the Unity console immediately fills with errors. It looks alarming because there are so many of them, but it's one problem reported many times over, and the fix is a single button click.

What actually went wrong

Unity has two input systems: the original one, usually called the old or default input system, and the newer Input System package. A project is configured to use one, the other, or both.

The project in this case was set up with the default input system. The first person character controller that was just imported is built against the new Input System. Those two don't coexist automatically, and the mismatch is what the console is complaining about.

The error is on the Event System

The errors point back to the Event System GameObject in the scene. Click on it and look at the Inspector, and you'll see the real message spelled out in full rather than repeated across dozens of console lines.

The message says, in effect: your project is using the old input system, you now have a GameObject in the scene that requires the new input system, and the project hasn't been updated to account for that. That one description is worth more than scrolling the console, because it tells you which component needs changing rather than just that something is broken.

The one-click fix

Unity provides a Replace button right there in the Inspector on the Event System. Click it.

That swaps the Standalone Input Module for the Input System UI Input Module, which is the equivalent component built for the new system. It's the exact change you would otherwise make by hand, so there's no reason to do it manually.

Clear the console and confirm

After hitting Replace, clear the console. All of those errors disappear at once, because they were all downstream of the same mismatch.

Clearing is an important step rather than a cosmetic one. Unity keeps old errors in the console until you clear them, so if you don't, you'll be staring at stale messages and assuming the fix didn't work.

Avoiding this next time

The general lesson: when you import an asset that brings its own input handling, check which input system it targets before you start debugging. Store pages and documentation almost always say.

If you're going to be mixing assets from both eras, you can set the project to support both under Edit, Project Settings, Player, in the Active Input Handling dropdown. That costs a little overhead but avoids the mismatch entirely.

And when a console fills up with a wall of red, resist the urge to read all of it. Errors cascade. Find the first one, or in this case click the object being complained about, and fix the root cause. One click usually clears the whole page.